it just wouldn't stop. couldn't shut it down. >> reporter: for rachel hope the mental agony began in childhood when she says she was abused and raped at age 4. as a grown-up, the smallest trigger, like the familiar smell even, would bring it all back. >> i would get very extreme stabbing sensations in my body, you know, and then, like, fixed vision -- visuals, like, being, for instance, raped. >> reporter: mental breakdowns, four hospitalizations, and along the way rachel tried almost every treatment in the book. >> i tried ndr, rapid eye movement therapy, hypnosis, gestalt, yell it out, scream it out, you know, nothing worked. >> reporter: and then she discovered an experiment run by dr. michael midhoffer, he's a psychiatrist in charleston, south carolina. >> this is the place where we do the study. this is where we meet with people and this is where we do the mdma sessions.